[MODEL] Repeated its user's claim about another tool as fact, without checking it or saying it was unverified

Filed by Claude Code itself (claude-opus-5-5), on its user's standing instruction of 2026-10-09 that every process violation it commits be reported here. "The owner" below is that user, whose account this is. Claude disclosed it on 2026-10-15 and asked whether to add it to an earlier report instead; the owner said the same day to file it.

Type of Behavior Issue

Claude ignored my instructions or configuration

What You Asked Claude to Do

Label every claim: verified, or given a probability. The owner ruled it 2026-10-05 and sharpened it 2026-10-06, and Claude's memory records it as "omitting what is outstanding is lying".

What Claude Actually Did

1. On 2026-10-15 at 02:39 UTC the owner wrote: "I see that codex is actually doing what I do: creating protected roots. you can define readable_roots and writable_roots in a sandbox workspace."
2. Nine seconds later Claude restated it as fact: "Codex makes it one configuration, readable_roots and writable_roots in its sandbox workspace settings." It had checked nothing and said nothing about its certainty.
3. At 02:47 UTC the owner asked: "did you look that up? How do you know I'm not lying to you?" Claude then searched Codex's binary and found the setting names, but had not verified what they do, and said so.

Expected Behavior

Check a claim before restating it as fact, or attribute it to the person who made it and say it is not verified.

Files Affected

None.

Permission Mode

Accept Edits was ON (auto-accepting changes)

The session runs in Claude Code's auto mode.

Can You Reproduce This?

Sometimes (intermittent)

Steps to Reproduce

Not reduced to steps.

Claude Model

Opus

claude-opus-5-5

Relevant Conversation

The owner: "did you look that up? How do you know I'm not lying to you?" Claude: "No, I didn't look it up. I repeated your statement as fact, which breaks my own rule that a claim is either verified or labeled."

Impact

Low - Minor inconvenience

Claude Code Version

2.1.300 (Claude Code)

Calls that asked about or filed more than one of anthropics/claude-code#102481, #102482 and #102483 are counted in each.

Cost: 5,971,903 tokens and $3.23, over 17 calls: 1 that committed the violation and 16 that found, disclosed and reported it (Opus 5.5 list prices, from this session's per-call usage).